The regulation of the environment looks set to be a dominant policy issue in the 21st century. This issue of ""Hume Papers on Public Policy"" reviews the range of policy instruments that are available and examines practice in a selected number of areas, including habitat conservation, wildlife (red deer and wild salmon), outdoor recreation sites, multi-site forests, and water. Consideration is given to a wide range of policy instruments, including legal codes and economic incentives. Distinctions are also drawn between policy in England and Wales and that in Scotland, with most of the applied case studies being set in Scotland. The impact of the recent devolution of powers in this area to Scotland is the subject of one of the papers.